Field of the Invention
This invention relates to applicators, in particular sponges and brushes distribute an application material such as makeup or paint onto a surface.
Description of the Prior Art
In the field of sponge and brush applicators, it is known that different materials have different properties for the application and distribution of application materials such as paints or cosmetics.
Natural application materials, such a bristles, whether of vegetable or animal origin, result from organic growth processes wherein elongated cellular formations build upon one another to form essentially rod-like structures of sufficient resilience and integrity to serve the functional needs required in brushes for painting, powdering, scrubbing, sweeping and the like. It is the cellular wall formation that provides structural character to these natural bristles along with the complex chemical makeup of the specific bristle. Some natural bristles are essentially tapered in that one end of the bristle is larger than the other. Others are not tapered or have very little of this tendency. Natural bristles are mostly irregular in shape along their length, and have scale-like outer surfaces. Some of these are naturally split at the end, forming tiny fingers which are useful in brush performance.
The use of the natural bristles, such as animal hair bristles however, has several significant drawbacks. Inconsistent supplies of natural bristles and unacceptable variations from one batch of bristles to another often impede manufacture of brushes having natural bristles. Natural bristles may also need to be treated for hygienic purposes to eliminate the presence of contaminants. Even if properly treated, many individuals are nevertheless allergic to natural bristles. In addition, natural bristles can be damaged by cleansing agents used to clean the bristles after use.
In view of these problems associated with the use of natural bristles, various attempts have been made to replace natural bristles with synthetic materials such as synthetic filaments made, for example, from polyamides (such as nylon) and polyesters. The use of synthetic bristles has also met with difficulties, however. Synthetic bristle materials usually have little of the cellular structures, shape irregularities or scale-like surfaces. Rather, they have dense polymeric structure and are highly uniform in shape, with smooth surfaces. Synthetic bristles are available in tapered or untapered form, and in cross-sectional profiles of solid round, hollow round, ribbed, S shaped and other shapes dependent on extrusion technology. Many synthetic materials require physical splitting of the ends (flagging) where this is deemed desirable in brushes and do not have the softness, texture and overall appearance of natural bristles.
Advances have been made where synthetic material more closely resemble the characteristics of natural materials. For example, synthetic bristles have advanced such that in the extrusion melt or process of a synthetic filament, certain other additives, sometimes called foaming or blowing agents, including nucleating materials, create tiny gaseous bubbles or other irregularities at random locations within the extruding filaments. In addition, blowing agents can be use in plastic parts manufactured by extrusion, injection and compression molding and other conventional plastic fabricating processes.
In addition to synthetic bristles resilient porous resilient materials such as sponges or foams may be used a material to comprise the application or blending elements.
In the field of cosmetics, these natural and synthetic materials have been used to apply cosmetics. For particular cosmetic uses, such as a typical Foundation Brush, these applicators are designed to retain powder, liquid or cream material from the material holder such as a compact and allow the user to transfer that material to the skin. The properties of the brush help retain the material and distribute it on the skin. A Blending Brush is used to blend the eye shadow color by moving the brush across the skin. This additional distribution of the material moves the liquid or powder around to make the color more even, and enables control over intensity and merging multiple colors in with one another.